Java web开发(16)Spring 和MyBatis整合开发(jar工程),MyBatis generator
基本配置
pom.xml文件内容
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.nothing</groupId> <artifactId>MybatisSpringFusion</artifactId> <version>0.0.1-SNAPSHOT</version> <properties> <spring.version>4.3.18.RELEASE</spring.version> </properties> <dependencies> <!-- 添加Spring支持 --> <!-- 核心包 --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>${spring.version}</version> </dependency> <!-- Spring IOC的基础实现,包含访问配置文件、创建和管理bean等 --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aop</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aspects</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>1.3.2</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>3.4.6</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.40</version> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.17</version> </dependency> <dependency> <groupId>commons-dbcp</groupId> <artifactId>commons-dbcp</artifactId> <version>1.4</version> </dependency> <dependency> <groupId>com.mchange</groupId> <artifactId>c3p0</artifactId> <version>0.9.5.2</version> </dependency> </dependencies> </project>
新建一个Source Folder ,叫config 里面添加,Spring,Mybatis 的配置内容
log4j.properties内容
# Global logging configuration #\u5728\u5f00\u53d1\u73af\u5883\u4e0b\u65e5\u5fd7\u7ea7\u522b\u8981\u8bbe\u7f6e\u6210DEBUG\uff0c\u751f\u4ea7\u73af\u5883\u8bbe\u7f6e\u6210info\u6216error log4j.rootLogger=DEBUG, stdout # Console output... log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.layout=org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n
SqlMapConfig.xml内容
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> </configuration>
applicationContext.xml文件内容
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd "> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="com.mysql.jdbc.Driver" /> <property name="url" value="jdbc:mysql://localhost:3306/hello" /> <property name="username" value="root" /> <property name="password" value="123456" /> <property name="maxActive" value="10" /> <property name="maxIdle" value="5" /> </bean> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 加载mybatis的配置文件 --> <property name="configLocation" value="SqlMapConfig.xml" /> <!-- 数据源 --> <property name="dataSource" ref="dataSource" /> </bean> </beans>
使用原始DAO方式开发
建立POJO类 User,UserDAO,UserDaoImpl
public interface UserDao { public User findUserById(int id)throws Exception; }
public class UserDaoImpl extends SqlSessionDaoSupport implements UserDao { public User findUserById(int id) throws Exception { //继承SqlSessionDaoSupport,通过this.getSqlSession()得到sqlSessoin SqlSession sqlSession = this.getSqlSession(); User user = sqlSession.selectOne("test.findUserById", id); return user; } }
在config文件夹中新建User.xml文件
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <!-- namespace命名空间,作用就是对sql进行分类化管理,理解sql隔离 注意:使用mapper代理方法开发,namespace有特殊重要的作用 --> <mapper namespace="test"> <select id="findUserById" parameterType="int" resultType="com.legion.ssm.dao.User"> SELECT * FROM USER WHERE id=#{value} </select> </mapper>
在applicationContext.xml文件添加
<bean id="userDao" class="com.legion.ssm.dao.UserDaoImpl"> <property name="sqlSessionFactory" ref="sqlSessionFactory"></property> </bean>
在SqlMapConfig.xml中添加
<mappers> <mapper resource="User.xml"/> </mappers>
测试代码
@Before public void setUp() throws Exception { applicationContext = new ClassPathXmlApplicationContext("classpath:applicationContext.xml"); } @Test public void testFindUserById() throws Exception { UserDao userDao = (UserDao) applicationContext.getBean("userDao"); //调用userDao的方法 User user = userDao.findUserById(10); System.out.println(user); }
Mapper代理开发
新建包com.legion.ssm.mapper,
新建UserMapper.java
public interface UserMapper { public User findUserById(int id) throws Exception; }
新建UserMapper.xml
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="com.legion.ssm.mapper.UserMapper"> <select id="findUserById" parameterType="int" resultType="com.legion.ssm.dao.User"> SELECT * FROM USER WHERE id=#{value} </select> </mapper>
在applicationContext.xml文件中添加
<!-- mapper批量扫描,从mapper包中扫描出mapper接口,自动创建代理对象并且在spring容器中注册 遵循规范:将mapper.java和mapper.xml映射文件名称保持一致,且在一个目录 中 自动扫描出来的mapper的bean的id为mapper类名(首字母小写) --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <!-- 指定扫描的包名 如果扫描多个包,每个包中间使用半角逗号分隔 --> <property name="basePackage" value="com.legion.ssm.mapper"/> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/> </bean>
测试代码
@Before public void setUp() throws Exception { applicationContext = new ClassPathXmlApplicationContext("classpath:applicationContext.xml"); } @Test public void TestMapper() throws Exception { UserMapper userMapper = (UserMapper) applicationContext.getBean("userMapper"); User user = userMapper.findUserById(1); System.out.println(user); }
逆向工程
目的:根据数据库自动生成Mapper代理的相关接口和配置代码,减少工作量。
添加相关jar包
<dependency> <groupId>org.mybatis.generator</groupId> <artifactId>mybatis-generator-core</artifactId> <version>1.3.5</version> </dependency>
新建generatorConfig.xml文件
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd"> <generatorConfiguration> <context id="testTables" targetRuntime="MyBatis3"> <commentGenerator> <!-- 是否去除自动生成的注释 true:是 : false:否 --> <property name="suppressAllComments" value="true" /> </commentGenerator> <!--数据库连接的信息:驱动类、连接地址、用户名、密码 --> <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://localhost:3306/hello" userId="root" password="123456"> </jdbcConnection> <!-- <jdbcConnection driverClass="oracle.jdbc.OracleDriver" connectionURL="jdbc:oracle:thin:@127.0.0.1:1521:yycg" userId="yycg" password="yycg"> </jdbcConnection> --> <!-- 默认false,把JDBC DECIMAL 和 NUMERIC 类型解析为 Integer,为 true时把JDBC DECIMAL 和 NUMERIC 类型解析为java.math.BigDecimal --> <javaTypeResolver> <property name="forceBigDecimals" value="false" /> </javaTypeResolver> <!-- targetProject:生成PO类的位置 --> <javaModelGenerator targetPackage="cn.itcast.ssm.po" targetProject=".\src"> <!-- enableSubPackages:是否让schema作为包的后缀 --> <property name="enableSubPackages" value="false" /> <!-- 从数据库返回的值被清理前后的空格 --> <property name="trimStrings" value="true" /> </javaModelGenerator> <!-- targetProject:mapper映射文件生成的位置 --> <sqlMapGenerator targetPackage="cn.itcast.ssm.mapper" targetProject=".\src"> <!-- enableSubPackages:是否让schema作为包的后缀 --> <property name="enableSubPackages" value="false" /> </sqlMapGenerator> <!-- targetPackage:mapper接口生成的位置 --> <javaClientGenerator type="XMLMAPPER" targetPackage="cn.itcast.ssm.mapper" targetProject=".\src"> <!-- enableSubPackages:是否让schema作为包的后缀 --> <property name="enableSubPackages" value="false" /> </javaClientGenerator> <!-- 指定数据库表 --> <table tableName="items"></table> <table tableName="orders"></table> <table tableName="orderdetail"></table> <table tableName="user"></table> <!-- <table schema="" tableName="sys_user"></table> <table schema="" tableName="sys_role"></table> <table schema="" tableName="sys_permission"></table> <table schema="" tableName="sys_user_role"></table> <table schema="" tableName="sys_role_permission"></table> --> <!-- 有些表的字段需要指定java类型 <table schema="" tableName=""> <columnOverride column="" javaType="" /> </table> --> </context> </generatorConfiguration>
使用配置的代码来生成Mapper文件
public class GeneratorSqlmap { public void generator() throws Exception{ List<String> warnings = new ArrayList<String>(); boolean overwrite = true; //指定 逆向工程配置文件 File configFile = new File("generatorConfig.xml"); ConfigurationParser cp = new ConfigurationParser(warnings); Configuration config = cp.parseConfiguration(configFile); DefaultShellCallback callback = new DefaultShellCallback(overwrite); MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings); myBatisGenerator.generate(null); } public static void main(String[] args) throws Exception { try { GeneratorSqlmap generatorSqlmap = new GeneratorSqlmap(); generatorSqlmap.generator(); } catch (Exception e) { e.printStackTrace(); } } }
对于这些生成的Mapper的使用实例
//插入 @Test public void testInsert() { //构造 items对象 Items items = new Items(); items.setName("手机"); items.setPrice(999f); itemsMapper.insert(items); } //自定义条件查询 @Test public void testSelectByExample() { ItemsExample itemsExample = new ItemsExample(); //通过criteria构造查询条件 ItemsExample.Criteria criteria = itemsExample.createCriteria(); criteria.andNameEqualTo("笔记本3"); //可能返回多条记录 List<Items> list = itemsMapper.selectByExample(itemsExample); System.out.println(list); } //根据主键查询 @Test public void testSelectByPrimaryKey() { Items items = itemsMapper.selectByPrimaryKey(1); System.out.println(items); } //更新数据 @Test public void testUpdateByPrimaryKey() { //对所有字段进行更新,需要先查询出来再更新 Items items = itemsMapper.selectByPrimaryKey(1); items.setName("水杯"); itemsMapper.updateByPrimaryKey(items); //如果传入字段不空为才更新,在批量更新中使用此方法,不需要先查询再更新 //itemsMapper.updateByPrimaryKeySelective(record); }
Eclispe中MyBatis Generator插件的安装使用:
1.安装:在Eclipse中点击Help =>Eclipse Marketplace,搜索Mybatis Generator 然后intall即可
2.使用。在source folder config 上右键,然后new other,找到Mybatis文件下的MyBatis Generator Configuration file
3.使用默认命名,generatorConfig.xml,
配置的参考代码
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd"> <generatorConfiguration> <context id="testTables" targetRuntime="MyBatis3"> <commentGenerator> <!-- 是否去除自动生成的注释 true:是 : false:否 --> <property name="suppressAllComments" value="true" /> </commentGenerator> <!--数据库连接的信息:驱动类、连接地址、用户名、密码 --> <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://localhost:3306/hello" userId="root" password="123456"> </jdbcConnection> <!-- <jdbcConnection driverClass="oracle.jdbc.OracleDriver" connectionURL="jdbc:oracle:thin:@127.0.0.1:1521:yycg" userId="yycg" password="yycg"> </jdbcConnection> --> <!-- 默认false,把JDBC DECIMAL 和 NUMERIC 类型解析为 Integer,为 true时把JDBC DECIMAL 和 NUMERIC 类型解析为java.math.BigDecimal --> <javaTypeResolver> <property name="forceBigDecimals" value="false" /> </javaTypeResolver> <!-- targetProject:生成PO类的位置 --> <javaModelGenerator targetPackage="com.legion.ssm.po" targetProject="SpringMVCMyBatisFusion/src/main/java"> <!-- enableSubPackages:是否让schema作为包的后缀 --> <property name="enableSubPackages" value="false" /> <!-- 从数据库返回的值被清理前后的空格 --> <property name="trimStrings" value="true" /> </javaModelGenerator> <!-- targetProject:mapper映射文件生成的位置 --> <sqlMapGenerator targetPackage="com.legion.ssm.mapper" targetProject="SpringMVCMyBatisFusion/src/main/java"> <!-- enableSubPackages:是否让schema作为包的后缀 --> <property name="enableSubPackages" value="false" /> </sqlMapGenerator> <!-- targetPackage:mapper接口生成的位置 --> <javaClientGenerator type="XMLMAPPER" targetPackage="com.legion.ssm.mapper" targetProject="SpringMVCMyBatisFusion/src/main/java"> <!-- enableSubPackages:是否让schema作为包的后缀 --> <property name="enableSubPackages" value="false" /> </javaClientGenerator> <!-- 指定数据库表 --> <table tableName="items"></table> <table tableName="orders"></table> <table tableName="orderdetail"></table> <table tableName="user"></table> <!-- <table schema="" tableName="sys_user"></table> <table schema="" tableName="sys_role"></table> <table schema="" tableName="sys_permission"></table> <table schema="" tableName="sys_user_role"></table> <table schema="" tableName="sys_role_permission"></table> --> <!-- 有些表的字段需要指定java类型 <table schema="" tableName=""> <columnOverride column="" javaType="" /> </table> --> </context> </generatorConfiguration>
注意:在Maven的Web项目中,targetProject是 项目名/src/main/java
不是其他所谓的.\src
4.生成代码:右键该配置文件,run as=>run MyBatis Generator